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Chinese Journal of chemistry 2024年第10期42卷 1107-1113页

作者： Guangyu Wang Huaiyuan Li Xuebing Leng Long Lu Qilong Shen key laboratory of fluorine and nitrogen chemistry and advanced materials Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling LuShanghai 200032China

The invention of a well-defined Cu(Ⅲ)fluoride complex Me_(4)N^(+)[Cu(CF_(3))_(3)(F)]^(-)1 enabled to access a versatile of functionalized Cu(Ⅲ)complexes[Me_(4)N]^(+)[Cu(X)(CF_(3))_(3)]^(-)(X=C_(6)F_(5),C_(6)F_(5)C≡C,CN,Cl,N_(3),^(t)BuOO,SCN,OAc,SAr),many of them for the first *** availability of these complexes allowed us to evaluate the trans-influence order of ligand in Cu(Ⅲ)complexes:Bn>CF_(3)^(-)>C_(6)F_(5)^(-)>N_(3)^(-)>py~CH_(3)^(-)~C_(6)F_(5)C≡C>NO_(2)PhO^(-)~^(t)BuOO^(-)~CH_(3)COO^(-)>F^(-).

关键词： fluorine Copper Cu(Ⅲ) Cu(Ⅲ)fluoride Trifluoromethyl

Combination of methylthio-chemistry with living crystallization-driven self-assembly toward uniformπ-conjugated nanostructures with antibacterial activity,surface tailorability,tunable morphology and dimension

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Science China chemistry 2024年第7期67卷 2341-2352页

作者： Chuyu Duan Binbin Xu Ruru Li Xiaoyu Huang Shaoliang Lin Chun Feng Shanghai key laboratory of advanced Polymeric materials School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China School of chemistry and materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China key laboratory of fluorine and nitrogen chemistry and advanced materials Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Living crystallization-driven self-assembly(CDSA)provides robust access to uniformπ-conjugated nanostructures(CNSs)from block copolymers(BCPs)containing a crystallineπ-conjugated segment with controlled dimension,morphology and composition,which show appealing applications in biomedicine,photocatalysis and *** further expand the application spectrum of these CNSs,the development of facile strategies toward diverse CNSs with varying structures/functionalities is highly ***,BCPs consisting of oligo(p-phenylene ethynylene)-b-poly(polypropyl-3-methanethiol acrylate)(OPE_(9)-bPMTPA35and OPE_(9)-b-PMTPA_(58);the subscript represents the number of repeat unit of each block)consisting of a crystallineπ-conjugated core-forming OPE_(9)segment and a corona-forming PMTPA block are *** efficient“click-type”alkylation of methylthio groups,OPE_(9)-b-PMTPA with varying contents of sulfonium unit is *** ribbon-like micelles with different widths and lengths can then be generated in a controlled manner via the self-seeding approach of living ***,negatively charged polymeric and Ag nanoparticles can be immobilized on sulfonium/methylthio-containing shells by taking advantage of electrostatic attraction and coordination interaction,***,the ribbon-like micelles with positively charged shells exhibit antibacterial activity against *** the ease of modification of PMTPA-based shell and attractive opto-electronic/photocatalytic properties ofπ-conjugated units,the combination of methylthio-chemistry and living CDSA opens a new avenue to generate multi-functional CNSs for widespread applications from biomedicine to photocatalysis.

关键词： crystallization-driven self-assembly block copolymer π-conjugated nanostructure methylthio-chemistry

Phase-transfer-shuttle generated in situ enables novel S1-type fluorination of sulfonium ylide with hydrofluoric acid

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Science China chemistry 2024年

作者： Yisa Xiao Rui Wang Zhaoxuan Xu Qunchao Zhao Renyi Pang Tao Dong Long Lu Qilong Shen key laboratory of fluorine and nitrogen chemistry and advanced materials Shanghai Institute of Organic Chemistry University of Chinese Academy Sciences Chinese Academy of Sciences

The development of a nucleophilic fluorination protocol using hydrofluoric acid as the fluoride source represents a long-sought goal in the field of organofluorine chemistry. We report herein the realization of such a reaction that employed alkyl-substituted sulfonium ylides as the substrates. The key to the success of the protocol was attributed to two factors: First, as a Br?nsted base,the ylide was able to be protonated by HFaq, thus serving as a phase-transfer shuttle generated in situ to bring F-from aqueous phase to the organic phase promoting desolvation of fluoride ion. Second, after protonation, a sulfonium salt, a good leaving group, was generated and subsequent attacked by the fluoride to afford the alkyl fluoride. Mechanistic investigation indicates that the reaction occurs via an SN1 pathway. Because of the nature of the cationic intermediate in the reaction, two attractive rearrangement-fluorination approaches including 1,2-aryl migration fluorination and ring-expansion fluorination were disclosed.

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Interfacial reinforcement of core-shell HMX@energetic polymer composites featuring enhanced thermal and safety performance

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Defence Technology（防务技术） 2024年第1期31卷 387-399页

作者： Binghui Duan Hongchang Mo Bojun Tan Xianming Lu Bozhou Wang Ning Liu Xi'an Modern chemistry Research Institute Xi'an710065People's Republic of China State key laboratory of fluorine&nitrogen Chemicals Xi'an710065People's Republic of China

The weak interface interaction and solid-solid phase transition have long been a conundrum for 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane(HMX)-based polymer-bonded explosives(PBX).A two-step strategy that involves the pretreatment of HMX to endow—OH groups on the surface via polyalcohol bonding agent modification and in situ coating with nitrate ester-containing polymer,was proposed to address the *** types of energetic polyether—glycidyl azide polymer(GAP)and nitrate modified GAP(GNP)were grafted onto HMX crystal based on isocyanate addition reaction bridged through neutral polymeric bonding agent(NPBA)*** morphology and structure of the HMX-based composites were characterized in detail and the core-shell structure was *** grafted polymers obviously enhanced the adhesion force between HMX crystals and fluoropolymer(F2314)*** to the interfacial reinforcement among the components,the two HMX-based composites exhibited a remarkable increment of phase transition peak temperature by 10.2°C and 19.6°C with no more than 1.5%shell content,***,the impact and friction sensitivity of the composites decreased significantly as a result of the barrier produced by the grafted *** findings will enhance the future prospects for the interface design of energetic composites aiming to solve the weak interface and safety concerns.

关键词： HMX crystals Polyalcohol bonding agent Energetic polymer Core-shell structure Interfacial reinforcement

Hydrodechlorination of trifluoro-trichloroethane to chlorotrifluoroethylene:Revealing the deactivation mechanism and regeneration strategy of Pd-Cu/AC catalyst

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Chinese Journal of Chemical Engineering 2024年第6期70卷 261-268页

作者： Song Tian Yicheng Chen Xiaoyu Wen Bingcheng Li Jian Lu Zile Li Feng Feng Qingtao Wang Qunfeng Zhang Xiaonian Li State key laboratory Breeding Base of Green chemistry Synthesis Technology Institute of Industrial Catalysis of Zhejiang University of TechnologyHangzhou 310014China State key laboratory of fluorine&nitrogen Chemicals Xi'an Modern Chemistry Research InstituteXi'an 710065China

Chlorotrifluoroethylene(CTFE)is a vital fluorinated olefinic monomer produced through the catalytic hydrodechlorination of trichlorotrifluoroethane(CFC-113),an eco-friendly ***,hydrodechlorination catalysts for olefin production often suffer from poor *** Pd/AC catalyst and Pd-Cu/AC catalyst prepared by co-impregnation method exhibited poor stability,Pd-Cu/AC catalyst with CFC-113 conversion dropping to around 37%after 50 h of hydrodechlorination ***-Emmett-Teller,transmission electron microscopy,X-ray photoelectron spectroscopy,and X-ray diffraction of fresh and deactivated Pd/AC catalysts indicate that the deactivation of Pd/AC catalysts is due to high-temperature agglomeration of *** analysis of fresh and deactivated Pd-Cu/AC catalysts using Brunauer-Emmett-Teller,transmission electron microscopy,and thermogravimetric analysis techniques revealed decreased dispersion of active sites,reduced surface area,catalyst aggregation deactivation,and a significant decrease in Cu ***,the results of NH3-TPD revealed that the acid sites of the catalyst increased significantly.X-ray diffraction spectra indicated the formation of new species,basic copper chloride(Cu_(2)(OH)_(3)Cl),during the *** the reaction progressed,these new species agglomerated,leading to a gradual loss of catalyst ***,the deactivated catalyst was successfully reactivated using a simple alkaline washing method.

关键词： CFC-113 Hydrodechlorination Chlorotrifluoroethylene Catalyst deactivation

Nucleophilic trifluoromethylation with CFH/LiHMDS:probing the nucleophilic reactivity of LiCFspecies

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Science China chemistry 2024年

作者： Yangfan Liu Xiu Wang Chuanfa Ni Jinbo Hu College of chemistry Central China Normal University key laboratory of fluorine and nitrogen chemistry and advanced materials Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of Sciences Chinese Academy of Sciences

The nucleophilic trifluoromethylation involving trifluoromethyllithium（LiCF3） species has been an open question since Haszeldine attempted to prepare LiCF3in 1949. Indeed, LiCF3has been used for electrophilic difluoromethylene transfer processes（via elimination of fluoride ions） since 2010. Herein, we demonstrated that by using a polar solvent such as dimethylformamide（DMF） or hexamethylphosphoramide（HMPA） as the lithium chelator, the in situ deprotonation of fluoroform（HCF3） with lithium hexamethyldisilazide（LiHMDS） could generate a tamed LiCF3species that is sufficiently persistent to undergo nucleophilic trifluoromethylation reaction. The nucleophilic reactivity of LiCF3species was probed with several electrophiles,including arylsulfonyl fluorides, diaryl ketones, and silyl chlorides. The synthetic utility of this method is demonstrated with the efficient synthesis of highly valuable triflones that are otherwise difficult to synthesize from HCF3using potassium or sodium bases. This work not only showcases a new protocol for the utilization of fluoroform（an industrial waste with high global warming potential） as the trifluoromethylation reagent, but also provides intriguing insights into the harnessing of nucleophilic reactivity of the transient LiCF3species.

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A novel Tb^(3+) and Eu^(3+) co-doped dual-emitting phosphate K_(3)SrBi(P_(2)O_(7))_(2) phosphor for application in FIR thermometers

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Journal of Rare Earths 2024年第3期42卷 455-463,I0001页

作者： Baochen Wang Shifeng Sun Zeqi Li Zongwang Li Weiwei Lin Chao Zeng Yan-gai Liu Ruiyu Mi School of Chemical and Environmental Engineering Anhui Polytechnic UniversityWuhu241000China State-Province Joint Engineering laboratory of Zeolite Membrane materials Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of EducationInstitute of Advanced MaterialsCollege of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China Beijing key laboratory of materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of GeosciencesBeijing100083China

Rare earth co-doped phosphor for fluorescence intensity ratio(FIR) thermometer has gained increasing attention in recent years. Herein, the novel Tb^(3+)and Eu^(3+)co-doped K_(3)SrBi(P_(2)O_(7))_(2)(KSBP) phosphate phosphors were reported. The crystal structure of the title phosphor was determined using Rietveld refinement and proved to have a three-dimensional structure. The time-resolved spectroscopy reveals that there is almost no energy transfer between Tb^(3+)and Eu^(3+). More importantly, Tb^(3+)and Eu^(3+)emissions show different thermal quenching behaviors, which claims the potential of this material for application in optical thermometer. The FIR of the typical KSBP:0.02Tb^(3+),0.04Eu^(3+)sample demonstrates a polynomial relationship as a function of temperature and the absolute and relative sensitivity are0.025 K^(-1) and 0.59%/K, respectively. In general, our study reports a novel and potential KSBP:Tb^(3+),Eu^(3+)phosphate phosphor that is promising for use in high-sensitive FIR thermometers.

关键词： Phosphor Thermometer Fluorescence intensity ratio Thermal stability Rare earths

Tunable Phase Structure of Side-chain Liquid Crystalline Polymers Enabled by Molecular Engineering of Dual Mesogenic Cores

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Chinese Journal of Polymer Science 2024年第10期42卷 1459-1469,I0009页

作者： Wen-Huan Yao Lan-Sheng Liu Jie Zhao Yan-Xia Wang An-Zhi Ma Zheng-Rui Ma Lan-Ying Zhang Ruo-Chen Lan College of chemistry and Chemical Engineering Hunan UniversityChangsha410082China key laboratory of Eco-Functional Polymer materials of the Ministry of Education Key Laboratory of Eco-Environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou730070China Department of materials Science and Engineering College of EngineeringPeking UniversityBeijing100871China Institute of advanced materials&key Lab of fluorine and Silicon for Energy materials and chemistry of Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China

A series of novel side-chain liquid crystalline(SCLC)copolymers were synthesized by attaching two distinct mesogenic units,namely a chiral cholesteryl-based monomer(M1)and an achiral biphenyl-based monomer(M2),to a poly(3-mercaptopropylmethylsiloxane)(PMMS)backbone via thiol-ene click *** influence of side chain composition on the self-assembly behavior and phase structures of these SCLC copolymers was systematically investigated using different *** indicate that three distinct liquid crystalline phases and four unique molecular configurations were identified within the polymer series,with the emergence of the liquid crystalline phase being a synergistic outcome of the two distinct side *** study underscores the critical influence of side chain dimensions,rigidity,and spatial volume on the self-assembly structures and phase characteristics of liquid crystalline polymers,providing valuable insights for the rational design and development of advanced functional materials with tailored properties.

关键词： Liquid crystalline copolymers Self-assembly Phase structure Chiral molar ratio

Acylfluorination of enynes via phosphine and silver catalysis

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Chinese Chemical Letters 2024年第8期35卷 260-264页

作者： Yu Mao Yilin Liu Xiaochen Wang Shengyang Ni Yi Pan Yi Wang State key laboratory of Coordination chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

This work describes intermolecular acylfluorination of gem-difluoroenynes using acyl fluorides as both acyl source and fluorine ***-substituted allenones or furans could be selectively achieved via phosphine and silve... 详细信息

关键词： Phosphine catalysis Silver catalysis Difunctionalization Allenone Furan Trifluoromethyl

Crystalline-amorphous M@MN_x(M=Co,Fe,Ni)encapsulated in nitrogen-doped carbon for enhanced efficient and durable hydrogen evolution reaction

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Rare Metals 2024年第4期43卷 1547-1556页

作者： Yang Yang Xiao-Chuan Duan Shao-Hui Guo Xian-Ming Zhang College of materials Science and Engineering College of ChemistryKey Laboratory of Interface Science and Engineering in Advanced MaterialsTaiyuan University of TechnologyYuci030600China

Developing earth-abundant electrocatalysts for hydrogen evolution reaction(HER)is important for the sustainable energy ***,efficient and stable heterocatalysts consisting of crystalline-amorphous M@MN_(x)(M=Co,Fe,Ni)encapsulated in N-doped carbon layers supported with N-doped graphene sheets(denoted as M@MN_(x)@NC-NG)are synthesized by facile hydrothermal reaction and nitridation *** the nitriding process,metal ions in M(tzbc)_2(H_(2)O)_4(tzbc=4-(1H-1,2,4-triazol-1-yl)benzoic acid)complexes are reduced to crystalline M cores,accompanied by the formation of amorphous MN_(x)shells;the tzbc ligands are insitu carbonized to form outermost N-doped carbon(NC)layers that connect with inner MN_(x)via M-N-C motifs inherited from the complex precursors and inhibit the transition of MN_(x)from amorphous to crystalline *** Co@CoN_(x)@NC-NG catalyst exhibits excellent HER activity with small overpotentials of 45 and 64 mV at a cathode current density of 10 mA·cm^(-2)and low Tafel slopes of 40 and 85 mV·dec^(-1)in 0.5 mol·L^(-1)H_(2)SO_4 and1.0 mol·L^(-1)KOH electrolytes,*** Co@CoN_(x)@NC-NG retains 97%of the initial overpotential after 100,000 s in both acidic and alkaline *** outstanding HER performance originates from the crystalline-amorphous Co@CoN_(x)that redistributes electrons around the heterointerfaces,facilitating the conversion process of H^(+)/H_(2)O to hydrogen and thereby promoting HER *** outermost NC layers serve as the armor of Co@CoN_(x),and graphene nanosheets act as carriers of egg-like Co@CoN_(x)@NC and conduction paths for electron shuttles,ensuring stable and continuous electrocatalytic hydrogen production.

关键词： Hydrogen evolution reaction Electrocatalysts Iron group metals Heterojunction Crystalline-amorphous structure